You've probably called a person by the wrong name. Misattributions are a pretty common way in which our memories are faulty. And they can take many forms. One of the more common is misattributing the source of an event. Your friend tells you about a tornado hitting a nearby community, and later that day you tell your husband you learned of the event from an online source.
Another form of misattribution involves matching the wrong face to a particular event. So you may be positive your sister was shopping with you the day your handbag was snatched, when you were really with your mother. Sometimes, you may even imagine an event, then later believe it actually occurred — misattributing fantasy to reality.
In one memory study, some people were asked to imagine performing an action, while others were asked to actually perform it. Later, the performing and imagining were repeated. Finally, the subjects were asked whether they had performed the action or merely imagined it. Many who had only imagined it were sure they had performed it. Interestingly, or perhaps shockingly, misattributing memories in these ways are considered to be a daily occurrence for most of us [source: PsyBlog].